OPEN Foundation

Day: 12 November 2020

The time course of psychotic symptom side effects of ketamine in the treatment of depressive disorders: a systematic review and meta-analysis

Abstract

Objective: Ketamine is a potential rapid-acting treatment for depression. Studies have suggested that the side effects are minimal and temporary, but the psychotic symptom side effects have yet to be fully examined. This study investigated whether ketamine infusion in the treatment of mood disorders is associated with increases in positive symptoms and whether these symptom effects endure over time.

Methods: A systematic review and meta-analysis of studies of ketamine in the treatment of depression. Embase and Medline databases were searched for studies including (a) participants with major affective disorders, (b) 0.4 or 0.5 mg intravenously administered ketamine, (c) measurement of positive symptoms using BPRS+, and (d) a within-subject repeated-measures design with participants serving as their own baseline.

Results: Seventeen studies met the inclusion criteria, comprising 458 participants. The meta-analyses examined symptom change occurring within the first 4 h, after 1 day, and after 3 days. Results showed significant BPRS+ increases within the first 30-60 min in 72% of studies, followed by a return to baseline levels.

Conclusion: Peak symptom change occurred within the first hour post infusion. There are limited data to determine if ketamine is safe in the longer term, but there were no indications that psychotic symptoms re-occurred after the first hour and in the days following administration.

Tashakkori, M., Ford, A., Dragovic, M., Gabriel, L., & Waters, F. (2021). The time course of psychotic symptom side effects of ketamine in the treatment of depressive disorders: a systematic review and meta-analysis. Australasian psychiatry : bulletin of Royal Australian and New Zealand College of Psychiatrists, 29(1), 80–87. https://doi.org/10.1177/1039856220961642

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Time is of the essence: Coupling sleep-wake and circadian neurobiology to the antidepressant effects of ketamine

Abstract

Several studies have demonstrated the effectiveness of ketamine in rapidly alleviating depression and suicidal ideation. Intense research efforts have been undertaken to expose the precise mechanism underlying the antidepressant action of ketamine; however, the translation of findings into new clinical treatments has been slow. This translational gap is partially explained by a lack of understanding of the function of time and circadian timing in the complex neurobiology around ketamine. Indeed, the acute pharmacological effects of a single ketamine treatment last for only a few hours, whereas the antidepressant effects peak at around 24 hours and are sustained for the following few days. Numerous studies have investigated the acute and long-lasting neurobiological changes induced by ketamine; however, the most dramatic and fundamental change that the brain undergoes each day is rarely taken into consideration. Here, we explore the link between sleep and circadian regulation and rapid-acting antidepressant effects and summarize how diverse phenomena associated with ketamine’s antidepressant actions – such as cortical excitation, synaptogenesis, and involved molecular determinants – are intimately connected with the neurobiology of wake, sleep, and circadian rhythms. We review several recently proposed hypotheses about rapid antidepressant actions, which focus on sleep or circadian regulation, and discuss their implications for ongoing research. Considering these aspects may be the last piece of the puzzle necessary to gain a more comprehensive understanding of the effects of rapid-acting antidepressants on the brain.

Kohtala, S., Alitalo, O., Rosenholm, M., Rozov, S., & Rantamäki, T. (2021). Time is of the essence: Coupling sleep-wake and circadian neurobiology to the antidepressant effects of ketamine. Pharmacology & therapeutics, 221, 107741. https://doi.org/10.1016/j.pharmthera.2020.107741

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Exploratory Controlled Study of the Migraine-Suppressing Effects of Psilocybin

Abstract

While anecdotal evidence suggests that select 5-hydroxytryptamine 2A (5-HT2A) receptor ligands, including psilocybin, may have long-lasting therapeutic effects after limited dosing in headache disorders, controlled investigations are lacking. In an exploratory double-blind, placebo-controlled, cross-over study, adults with migraine received oral placebo and psilocybin (0.143 mg/kg) in 2 test sessions spaced 2 weeks apart. Subjects maintained headache diaries starting 2 weeks before the first session until 2 weeks after the second session. Physiological and psychological drug effects were monitored during sessions and several follow-up contacts with subjects were carried out to assure safety of study procedures. Ten subjects were included in the final analysis. Over the 2-week period measured after single administration, the reduction in weekly migraine days from baseline was significantly greater after psilocybin (mean, – 1.65 (95% CI: – 2.53 to – 0.77) days/week) than after placebo (- 0.15 (- 1.13 to 0.83) days/week; p = 0.003, t(9) = 4.11). Changes in migraine frequency in the 2 weeks after psilocybin were not correlated with the intensity of acute psychotropic effects during drug administration. Psilocybin was well-tolerated; there were no unexpected or serious adverse events or withdrawals due to adverse events. This exploratory study suggests there is an enduring therapeutic effect in migraine headache after a single administration of psilocybin. The separation of acute psychotropic effects and lasting therapeutic effects is an important finding, urging further investigation into the mechanism underlying the clinical effects of select 5-HT2A receptor compounds in migraine, as well as other neuropsychiatric conditions. Clinicaltrials.gov : NCT03341689.

Schindler, E., Sewell, R. A., Gottschalk, C. H., Luddy, C., Flynn, L. T., Lindsey, H., Pittman, B. P., Cozzi, N. V., & D’Souza, D. C. (2021). Exploratory Controlled Study of the Migraine-Suppressing Effects of Psilocybin. Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics, 18(1), 534–543. https://doi.org/10.1007/s13311-020-00962-y

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Ketamine in Bipolar Disorder: A Review

Abstract

Bipolar disorder (BD) is a psychiatric illness associated with high morbidity, mortality and suicide rate. It has neuroprogressive course and a high rate of treatment resistance. Hence, there is an unquestionable need for new BD treatment strategies. Ketamine appears to have rapid antidepressive and antisuicidal effects. Since most of the available studies concern unipolar depression, here we present a novel insight arguing that ketamine might be a promising treatment for bipolar disorder.

Wilkowska, A., Szałach, Ł., & Cubała, W. J. (2020). Ketamine in Bipolar Disorder: A Review. Neuropsychiatric disease and treatment, 16, 2707–2717. https://doi.org/10.2147/NDT.S282208

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30 April - Q&A with Rick Strassman

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